In today's pollution-conscious society, noise pollution is receiving ever-increasing attention. In heavily populated areas, for example, the noise level deriving from vehicular traffic alone is reaching staggering proportions. To this can be added the effects of industrial noise and the noise which inevitably accompanies the construction activities to be found in every metropolitan area. The problem has become so acute that the U.S. Government has established a special agency (The Environmental Protection Agency) to deal with it.
Of particular concern for purposes of the present invention is the noise pollution which the construction industry generates, and, in particular, the noise pollution associated with heavy equipment, such as pile drivers. The present invention, therefore, deals with noise abatement, and, in particular, with noise abatement in heavy equipment, such as pile drivers.
Sound distribution studies on pile drivers have shown that the greatest intensity of noise is developed in the area where the hammer ram strikes the anvil or drive cap. From this point of impact the noise travels diminishingly down the pile that is being struck and to a lesser extent up the body or cylinder of the hammer and then to the leads frame. In addition, the noise propogates at the same time through the air in all directions. It would be desirable, therefore, to have a way of effectively abating the noise developed as a result of operating a machine such as a pile driver.
An added problem with which the construction industry has had to contend with is that of pile hoisting. At the present time it is necessary to employ a so-called "loft man" whose job is to ascend approximately midway to the top of the pile, just under the hammer. This is the dangerous part, because the hammer falls too fast when the pile is resting on soft ground, for example. Thus the hammer can crush the man. The "loft man" is necessary in order to correctly align the pile to be driven with respect to the drive hammer. This type of manual operation is time-consuming, fatiguing, and, as indicated above, quite dangerous. It would be desirable, therefore, to have a way of effectively eliminating the need for a "loft man".